2 Answers
2

If you create a USB 'LiveCD' from within Ubuntu, it will nearly always work. You only have to be concerned with disparity between the version of Ubuntu used to create and the version being installed. This can cause issues similar to what you are experiencing.

You are far more likely to have issues with USB 'boot' and 'kernel', with a third-party USB creator application.

Fail Safe Approach

( until you have a nearby Ubuntu 12.04 to use 'Startup Disk Creator'. )